1. Field of the Invention
The invention relates to polyurethane elastomer films containing dispersed discrete aggregates of liquid cystals.
2. Description of the Prior Art
Polyurethane elastomer films containing dispersed discrete aggregates of liquid crystals are described in U.S. Pat. No. 3,872,050. Polyurethane films prepared in accordance with that patent exhibit useful visible color responses at selected temperature ranges or when exposed to mechanical stresses or both--according to the specific composition of the dispersed liquid crystal phase. In accordance with that patent, it is possible to disperse more than 20 percent by weight of the film as discrete aggregates of liquid crystals. Nevertheless there remains a need for further improvement in the visual color response of such films.